Quantitative microbiological risk assessment

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Quantitative microbiological risk assessment [1] (QMRA) is the process of estimating the risk from exposure to microorganisms.

The process involves measuring known microbial pathogens or indicators and running a Monte Carlo simulation to estimate the risk of transfer. [1] If a dose-response model is available for the microbe, it be used to estimate the probability of infection.

QMRA has expanded to be used to estimate microbial risk in many fields, but is particularly important in assessments of food [2] water supply [3] and human faeces/wastewater safety. [4]


Risk assessment relative to the other activities of risk analysis1 3circles diagram color.jpg
Risk assessment relative to the other activities of risk analysis1

QMRA to assess safety of sanitation systems

The World Health Organisation's 2006 Guidelines for the Safe Use of Wastewater, Excreta and Greywater in Agriculture suggest that QMRA should be used to determine possible risk levels which can be achieved by sanitation systems. [5]

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References

  1. 1 2 Haas, Charles (1999). Quantitative Microbial Risk Assessment. New York: Wiley. ISBN   0-471-18397-0.
  2. Pérez-Rodríguez, Fernando; Valero, Antonio (2013). Predictive Microbiology in Foods. pp. 1–10. doi:10.1007/978-1-4614-5520-2_1. ISBN   978-1-4614-5519-6.
  3. Smeets, P. W. M. H.; Rietveld, L. C.; van Dijk, J. C.; Medema, G. J. (2010). "Practical applications of quantitative microbial risk assessment (QMRA) for water safety plans". Water Science & Technology. 61 (6): 1561–8. doi: 10.2166/wst.2010.839 . ISSN   0273-1223. PMID   20351436.
  4. Harder, Robin; Heimersson, Sara; Svanström, Magdalena; Peters, Gregory M. (2014). "Including Pathogen Risk in Life Cycle Assessment of Wastewater Management. 1. Estimating the Burden of Disease Associated with Pathogens". Environmental Science & Technology. 48 (16): 9438–9445. Bibcode:2014EnST...48.9438H. doi:10.1021/es501480q. ISSN   0013-936X. PMID   25058492.
  5. Drechsel, Pay (2010). Wastewater Irrigation and Health: Assessing and Mitigating Risk in Low-income Countries. IWMI. pp. 387–. ISBN   978-1-84407-796-0 . Retrieved 11 April 2015.